Process for granulating metals



Patented 21 1942 PROCESS FOR ammo: I I oaannumc METALS Russell net-t, Los A ngeles, Calif. No Drawing. Application March 21, 1941,

a set-m 0. seem 7 Claims. (CI. 83-91) 1 The chief object of this invention is to provide a practical process to granulate metals, and in particular the easily oxidizable metals such as sodium, potassium, lithium, etc. and their alloys,

without excessive oxidization. A secondary obiect is to produce the metallic granules in such a way that they tend toassume form. v

A I will now describe a method to granulate metallic sodium.

I melt thesodium metal in an iron kettle unider a suitable hydrocarbon oil such as pure parafiine base, 8. A. E. 50, lubricating oil and then raise the temperature to and maintain at about 125 degrees C. In a second kettle I have pure parafilne base, 8. A. E. 50, lubricating oil maintained at a temperature of about 125 degrees-C.

1 have a third kettle preheated to about 125 degrees C. into which I pour about ten pounds oi molten sodium from the first kettle and about stir, beat or mix the mixture of oil and molten sodium until the molten sodium assumes the form of globulesfloi the desired fineness. The longer and more vigorous the beating or mixing, the finer the sodium globules become. globules of the desired fineness is obtained, the hot mixture of molten globular sodium and oil is run into a barrel containing cold dry kerosene or other suitable hydrocarbon or liquid. The quan-,

the spherical cold'kerosene or other suitable hydrocarbon and then remelting it under oil and beating or mixing it with oil as described above. In this manner I have made up to V .inch diameter shot and downto 1/100 inch diameter globules. suitable power beater or mixer there is no reason wny 1/1000 inch diameter globules cannot be produced.

I have described how to produce sodium glo ules or shot.- It is apparent that other metals such as potassium, lithium, tin, bismuth, lead,

zinc, cadmium, aluminum, various alloys, etc.

can be granulated by this process. To granulate any of these metals or alloys, the metal is melted and-then heated about deg. C. above its melting point and then beaten or mixed with a suitsure all, grease or other substance liquid at the 5 pounds of oil from the second kettle and then a, When" tity and temperature or the kerosene should be such that after the hot sodium oil mixture is added to it, the combined temperature or the sodium-oil-kerosene mixture should not rise'to over-60 degrees C. I have used ten gallons of kerosene at a temperature of 25 degrees C. to

cool 10 pounds of sodium globules. It the kero-.

sene bath is allowed to get too hot there is a tendency for the sodium globules to weld together to form an oolitic mass. The function of the oil or grease is to cover themolten sodium globules and hence to keep the globules from coalescing. The quantity of oil or grease to use per pound otsodium will vary with the fineness of sodium globules desired. For example, suppose we desire V; to V inch of sodium is suillcient. Should we desire sodium globules oi 1/100 inch in diameter, then we should use 7 to 10 pounds of oil to '10 pounds or sodium.

I have discovered that the molten sodium some diameter shot, then 2.pounds oi oil to 10 pounds times has a tendency to form irregular shaped granules and resists becoming globular. When thishappensthedifilcultyeanbeovercomeby melting the sodium under oil and into melting point of the metal used, and'then pouring the mixture into a suitable cooling liquid.

Any type of stirrer, beater. or mixer can be sirable to use a suitably designed mixer or beater.

Having described my invention, 1 now claim:

1.;The process for granulating'the alkali metals" which consists of melting the .metal under a suitably non-reactive liquid having a boiling point above the melting point of said metal and then mixing or beating the mixture until the molten metal is granulated to the desired fineness and then pouring the beaten mixture into a suitably non-reactive cooling liquid maintained at a temperature below the melting point or the metal to solidify the metallic granules.

2. The process for granulating an alloy of alkali'rnetals which consists-of melting the alloy under a suitably non-reactive liquid having a boiling point above the melting point of said alloy and then mixing or beating the mixture until the molten alloy is granulated to the required fineness and then pouring the beaten mixture into a suitably non-reactive cooling liquid maintained at a temperature below the melting point of the then mixing 'or'beating the mixture until the molten alloy is granulated to the desired fineness and then pouring the beaten mixture into a suitably non reactive cooling liquid maintained at With a a temperature below the melting point of said alloy to solidify the metallic granules.

4. The process for granulating metallic sodium which consists of melting the metal under a suitably non-reactive liquid having a boiling point above the melting point of sodium and then mixing or beating the mixture until the molten sodium is granulated to the desired fineness and then pouring the beaten mixture into a suitably non-reactive cooling liquid maintained at a temperature below the melting point of sodium to solidify the metallic granules.

5. The process for granulating metallic sodium which consists of melting the sodium under a hydrocarbon oil having a boiling point above the melting point of sodium and then mixing or beating the mixture until the molten sodium is granulated to the desired fineness and then pouring the beaten mixture into a suitable hydrocarbon cooling liquid maintained at a temperature below the melting point of sodium to solidify the metallic granules.

tallic granules.

7. Theprocess for granulating an alloy containing 1 to 10% potassium and 90 to 99% sodium which consists of melting the alloy under a hydrocarbon liquid having av boiling point above the melting point of the alloy and then mixing or beating the mixture until the alloy is granulated to the desired fineness and then pouring the beaten mixture into a hydrocarbon cooling liquid maintained at a temperature below the melting point of the alloy to solidify the me- RUSSELL HART. 

